Apparatus for trimming of the ends of cans and the like to form a smooth and uniform rim are well known in the art. These apparatus frequently employ a knife mounted about a spindle, over which the can is positioned, which cooperate with an externally positioned knife to trim the uneven metal from the rim. External holding means to the can are generally employed to hold the can in place during the trimming operation. A frequent problem often encountered, however, is the formation of slivers and steps since the can tends to move during trimming. This is unacceptable to the quality of the can and thereby causes rejects. By applicant's invention, however, this problem is eliminated, as described hereinafter.